New York was second, attracting $18.6 billion, followed by California, with $15.7 billion.

From 2002 to 2011, private-equity firms have invested an estimated $246.9 billion in Texas-based companies.

The study also found that nearly 1,500 Texas companies, supporting 535,800 workers in and outside the state, have received private-equity backing.

The PEGCC released analysis of the private-equity investments of 75 the largest state pension plans in the U.S. Those plans managed more than $2.4 trillion in assets and represent nearly 17.8 million active and retired beneficiaries.

It found that Teacher Retirement System of Texas’ 10-year return on private-equity investment was 13.1 percent. Only the Commonwealth of Pennsylvania Employees’ Retirement System, with a 13.6 percent return, was higher.

The PEGCC has posted online an interactive map that aggregates state-by-state information about large public pension plans and their investments in private equity.

Private-equity firms, such as Bain Capital, Mitt Romney’s former firm, have come under scrutiny, accused by critics of stripping companies of their assets, saddling them with debt and laying off workers. The PEGCC counters that private-equity adds value to portfolio companies.